Secret No More: FBI Central Records Systems Classification

The first three numbers of any FBI file designation indicate the kind of offense the FBI was investigating when it opened the file. For example, a file number that begins “025” would be classification 25, or an investigation into draft evasion or violation of the Selective Service Act.

1

National Academy matters

2

Neutrality Matter

3

Destruction or Overthrow of the Government

4

National Firearms Act

5

Income Tax

6

Interstate Transportation of Strikebreakers

7

Kidnapping

8

Migratory Bird Act

9

Extortion

10

Red Cross Act

11

Tax (other than income)

12

Narcotics

13

National Defense Act; Prostitution; Selling Whiskey Within Army Camps, 1920 only (obsolete)